Three experimental models of neural trauma are being studied. (1) Inertial loading in a subhuman primate validating a mathematical model which will be used for developing improved standards for head injury protection and prevention. (2) A series of studies on isolated neural tissues correlating the primarily neural effects of the trauma independent of the vascular system. (3) A model is of spinal cord injury. This is a modification of a recently published spinal cord crush injury developed in the dog which we have adapted for the rhesus monkey. We are evaluating the regenerative capacity of the primate spinal cord in this model using peripheral nerve and cultured Schwann cell grafts with and without additional therapy using pulsed radiofrequency energy. Clinical studies on neural trauma are being carried out in collaboration with GWUMC aimed at correlating the in-vivo neuropathology as seen on C.T. scans in head injury patients with the clinical data and in selected cases with the post-mortem neuropathology. Selected patients with paraplegia are also being evaluated for extent of neural and vascular damage. BIBLIOGRAPHIC REFERENCES: Ommaya, A.K., Murray, G., Ambrose, J., Richardson, A. and Hounsfield, G.: Computerized axial tomography: estimation of spatial and density resolution capability. Br. J. Radiol. 49: 604-611, 1976. Wood, J.H., Parver, M., Doppman, J.L. and Ommaya, A.K.: Experimental intraoperative localization of retained intracerebral bone fragments using transdural ultrasound. J. Neurosurg. 46: 65-71, 1977.